Question

एक बंदर एक खम्भे पर पहले मिनट में 12 मीटर चढ़ता है,एवं अगले मिनट में 5 मीटर नीचे फिसल जाता है यदि खंभे की ऊँचाई 63 मीटर हो तो बन्दर कितने समय मे खम्भे की चोटी पर पहुंच जाएगा।।​

Answer 1

in 9 mins he could reach at the top

Answer 2

Answer:

In 1 minute the monkey climbs 12 meters but then he takes 1 minute to slip down 5 meters. So, at the end of 2 minutes the net ascending of the monkey is 12 - 5 = 7 meters

So, to cover 63 meters the above process is repeated 63/7 = 9 times.

Obviously, in 9 such happenings the monkey will slip 8 times because on 9th time it will climb to the top

Thus in climbing 8 times and slipping 8 times, he covers 8 × 7 = 56 meters

Remaining distance = 63 – 56 = 7 meters

Time taken to ascend 7 meters = 7/12 meters

Total time taken = 16 + 7/12 minutes

= 16 minutes 35 seconds